Remote control circuit breakers are commonly used for temporary interruption of electrical service during peak use hours and for programmable lighting control of industrial locations. By opening and closing on demand from a remote location, these circuit breakers provide a significant improvement over manually operated circuit breakers in terms of convenience.
A variety of operating mechanisms have been employed to realize remote control of circuit breakers. One of the more common types of remote control mechanisms energizes a solenoid to hold the circuit breaker in the open position. Such energization must be continuous to prevent the circuit breaker from moving to the closed position.
Improved remote control mechanisms have included the use of a motor to operate the opening or closing of the contacts. The motor is coupled to one of the contacts through a gear, which rotates simultaneously with the shaft of the motor to cause the circuit breaker contacts to open and close.
Further improved remotely controlled circuit breaker mechanisms are disclosed in U.S. Pat. No. 5,180,051 entitled "Remote Controlled Circuit Breaker" and U.S. Pat. No. 5,532,660entitled "Manual Override Mechanism for a Remote Controlled Circuit Breaker" which are assigned to the same assignee as the present application and the disclosures therein are incorporated herein by reference. The remote controlled circuit breaker disclosed in these patents includes a gear driving means responsive to OPEN and CLOSE control signals generated from a remote location for moving a moveable one of a pair of electrical contacts through associated gear means in order to correspondingly interrupt or establish a circuit path.
In all such remote controlled circuit breaker mechanisms, it is desirable to provide an override mechanism for manually controlling the circuit breaker when necessary by disabling or overriding the remote control mechanism for the circuit breaker. U.S. Pat. No. 5,532,660provides an example of such an override mechanism. However, mechanisms of this type may not operate as efficiently as necessary.
The remote control mechanism in U.S. Pat. No. 5,532,660 includes a slide mechanism which is coupled to a gear for enabling and disabling the remote control mechanism. The slide mechanism and the gear are movable between a fixed position, which renders the remote control mechanism responsive to remote control signals and a non-fixed position, which allows free movement thereof and renders the remote control mechanism non-responsive to the remote control signals.